The problem of alignment is an old and complex one. If a player really wishes to use his character's alignment to guide him in play, he may find the paragraphs pertaining to alignment in the game rules to be too general and difficult to apply. The solution to this difficulty lies with the gaming group and DM, who have the authority to define specifically what is meant by each alignment in the context of the particular campaign. There is another difficulty involved in using alignment in role-playing. A chaotic character may realize that acting on his own behalf would destroy the group and all its members. Is he playing out of character by going along with the others? A lawful character may feel compelled to obey a senseless command, a good character may have to kill to survive, and so on. Many players feel that there is often a conflict between "playing in alignment" and playing intelligently (we've all heard and witnessed the phrase "Lawful Stupid"). This dilemma is not a real dilemma. It comes from considering the requirements of alignment too superficially and not integrating alignment with intelligence and wisdom to produce a consistent character. Intelligence dictates the degree to which a character's outlook (alignment) is rationalized. An unintelligent chaotic merely resents being bossed around, whereas an intelligent chaotic consciously espouses some philosophy, such as anarchism or existentialism, that promotes the individual over the group. These two chaotics will act quite differently if given an order. The unintelligent chaotic will resent any order and will probably have to be physically coerced if what is asked of him is in any way difficult or dangerous. The intelligent chaotic, on the other hand, will readily obey any order that he considers to be logical and in his own best interest. He may resist authority that he believes to be in error, although he is open to persuasion if any one can convince him that he will ultimately benefit from obedience. He will never consider obedience beneficial as an end in itself, but as a means to personal advancement he will accept it. The following notes summarize how intelligence and alignment can affect a PC's personality:

Intelligence of 7 or lessThe character's alignment is inarticulate and unrationalized. He cannot give reasons for his behavior, but he acts on his natural inclinations. A neutral character of low intelligence is easily swayed by circumstance and peer pressure. A chaotic character is contrary, while a lawful one is docile and obedient. A good character is naturally sympathetic and helpful toward anyone he meets, while an evil character dislikes everyone equally.

Intelligence of 8-11This character has at least some rational justification for his alignment tendencies. A good character may quote the golden rule or appeal to the authority of the prevailing culture. An evil character may take a "do unto others before they do it to you" attitude. A lawful character will point to the stabilizing effects of order, while a chaotic one may condemn law as a first step to slavery. A neutral character will be motivated by a simple kind of relativism ("It takes all kinds."). Characters of average intelligence can be persuaded from their natural inclinations only with some difficulty, force or threat often being more effective than words.

Intelligence of 12-15A character in this category belongs to some specific philosophical school or holds some specific religious doctrine. He will discuss his principles and attempt to apply them when an important decision arises. However, he usually has a number of uncertainties regarding the philosophy he holds and is readily persuaded to take the most sensible course of action when in doubt. A chaotic character would speak in terms of individual rights and freedom, but a lawful character would appeal to a principle such as the divine right of kings. A good character will seek the greatest good for the greatest number and will have some interest in the survival of good on the large scale, rather than just an inclination toward generosity. An evil character will see history as a pattern of force and will measure success by the injury done to opponents.

Intelligence of 16-17A highly intelligent character will have a detailed personal philosophy, often of his own devising. His justifications for his actions will be well reasoned and distinctive. Much of his life's goal consists of the creative realization of his philosophy. Many such characters are quite subtle, seeking to achieve some grand design that is not obvious to others. However, some find an intellectual challenge in holding to a strict code of ethics at all times. A good character of this latter sort might go to great lengths to survive a battle without taking another's life or shedding blood.

Intelligence of 18 or aboveSuch a genius character is a philosopher with a detailed moral system of his own devising (or at least his own unique interpretation of an existing system). Most such characters will endeavor to become philosopher-kings, found religions, or establish places of learning from which to put forth their ideas. They are looked upon as spokesmen for their alignments.

One grievance I have with this, and note that I have no real experience with D&D or its rulesets, I speak from my point of view:

Wouldn't this make more sense with Wisdom than Intelligence?

Intelligence as defined by google: the ability to acquire and apply knowledge and skills.

Wisdom as defined by google: the quality of having experience, knowledge, and good judgment.

Would it not make more sense that one with a lot of Wisdom, would have the experience, knowledge, and good judgment to understand the intricacies of their alignment and what would be appropriate action within it? Another thing I would like to cite is the description of the Wisdom attribute per Neverwinter Nights character creation:

"Wisdom describes a character's willpower, common sense, perception, and intuition, whereas intelligence represents the ability to analyze information. An "absent-minded professor" has low wisdom and high intelligence. A simpleton with low intelligence might nevertheless be very perceptive (have high wisdom). "

Again, I am no D&D ruleset expert, but I feel that Wisdom is a very underrated attribute when it comes to roleplaying. For a game example of what I'm driving at, I recommend playing Planescape: Torment, if you have not already. The game in itself drives the point home of how overlooked Wisdom gets for these kinds of situations.